Funds are requested to support new projects in the Monell-Jefferson Chemosensory Clinical Research Center CCRC). This CCRC involves a collaboration between scientists at the Monell Chemical Senses Center and physicians at Thomas Jefferson University. Collaborative ties also exist with physicians and scientists at the University of Pennsylvania, several other Universities, and the Veterans Affairs Medical Center of Philadelphia. It is devoted to the scientific examination of clinical disorders in taste, smell and chemical irritation. Through the multidisciplinary study of clinical populations, the goals of CCRC scientists are to characterize and understand the etiologies of disorders in chemosensory function, provide information on mechanisms and functions of the chemical senses in humans, and develop strategies for treating/coping with chemosensory disorders. The CCRC entails an Administrative Core unit, a Sensory/Medical Core unit and three individual yet highly interrelated research Projects. The general aims of each of the three Projects, respectively, are to: 1) Evaluate the causal factors underlying smell loss in patients with chronic rhinosinusitus, such as alterations of air flow and odor deposition, peri-receptor factors, and inflammatory mediators, and establish the prognosis for recovery in these patients;2) Prospectively evaluate the inflammatory impact of chronic inhalant exposure to chemicals and particulates on nasal chemosensory function, explore mechanisms of action, and use computational models of air flow to predict olfactory function following changes in nasal structure;3) Document the magnitude, quality and time course for changes in taste perception following radiation treatment for oral cancer, and explore the bases for disruption and the prognosis for recovery, through the examination of the impact of inflammatory factors on gustatory tissue at the molecular and cellular levels. Thus, in each of the three Projects the role of inflammatory factors in mediating sensory loss and recovery will be investigated. Tying these projects together through patient recruitment, common psychophysical and medical assessment, and coordination of database management and statistical evaluation is the Sensory/Medical Core. This Core will also continue to evaluate patients referred with primary complaints of chemosensory dysfunction in order to identify additional questions of clinical interest and to refine hypotheses concerning the nature, bases and implications of those dysfunctions.